This invention relates to a data converting device for converting the size, etc, of inputted data. More particularly, the present invention relates to a data converting device functioning as a relay for relaying multimedia data transmitted through a plurality of kinds of transmission media, such as image, speech data, sound-attached moving-picture data etc, a data transmission method, and an information storage medium storing a data conversion function.
In network systems in general, services are offered among a plurality of information processing units connected to the network.
In this case, the information processing unit on the service requesting side is referred to as a xe2x80x9cclientxe2x80x9d and the information processing unit on the service offering side, a xe2x80x9cserverxe2x80x9d.
T. Berners-Lee et al., xe2x80x9cCommunications of ACMxe2x80x9d, Vol. 37, No. 8, pp. 76-82(1994) published by ACM Press describes an example of multimedia network systems for describing screen configuration mainly by character strings in a wide area network system.
Such a multimedia network system has spread in world-wide networks and access to world-wide information can be acquired by making access to the servers in the world.
The capacity of data handled in the multimedia network system, such as static images, moving images, speech, and so forth, is by far greater than that of texts.
Therefore, when the multimedia network system is utilized in the environment having a small network transmission capacity, the problem develops in that an extremely long time is necessary for the data transfer.
When the amount of data transmitted from the server to the client is reduced, the data access time can be reduced particularly when the transmission rate of the network is low, and the user can gain access to a greater amount of information within a predetermined time.
When the data converting device described above is used, the data access time can be reduced as a result of the reduction of the data transmission amount between the server and the client, but layout of the screen display is changed when button display is employed for indicating the reduction of a static image in the screen display, etc.
If layout of the screen display itself has information such as a table, such a change of layout means the loss of information and deteriorates appearance of the design. See FIG. 9 (902, 903 and 904). In FIG. 8, screen configuration data 801, description 802 of the image tag, and descriptions 803 and 804 of the anchor tags are shown.
To look up the screen display in accordance with original screen configuration information transmitted by the server, the user of the client must stop utilization of the data converting device. Because the method of stopping the utilization of the data converting device requires the change of setting of the client, this operation is much more complicated than the normal button selection operations, and another problem arises in that operation efficiency drops when the user frequently desires to switch the utilization and to stop the data converting device.
When a large number of buttons for looking up the static image are disposed in the screen display, the display area of the screen becomes lack of information, and still another problem occurs in that the screen display becomes redundant for the user who seldom makes access to the additional buttons.
It is an object of the present invention to provide a data converting device which converts data transmitted from a server to data which considers performance of the client, a transmission medium connected to the client, etc, and causes the client to receive this data, a network system equipped with such a data converting device, and a data transmission method.
It is another object of the present invention to provide a data converting device which instructs a user of a client to control a conversion processing of multimedia data and enables the user to carry out the data conversion processing in accordance with this instruction, a network system equipped with such a network, and a data transmission method.
To accomplish the objects described above, a data relay apparatus connected between a server device and a client device includes a command analysis portion for analyzing a command inputted from the client device, which analysis portion reads out and stores conversion instruction information when the command contains the conversion instruction information instructing a predetermined data conversion processing; a request portion for deleting the conversion instruction information from the command and sending it to the server device; a detection portion for receiving data sent from the server device, which detection portion converts the data on the basis of the conversion instruction information stored and add the conversion instruction information to the reference address included in the description referring to a text data included in other data; and a transmission portion for transmitting the data and the result of the added information to the client device.
The conversion instruction information can contain a screen configuration command for instructing to divide the area of the screen displayed on the client device into a reception data display area for the data received from the server device and an operation area for the screen operation. The data relay apparatus can further contain a first expansion portion for expanding the display data from the server device on the reception data display area on the basis of the screen configuration command and a second expansion portion for expanding the operation buttons corresponding to another screen configuration command indicating contents of transformation on data in the operation area in accordance with the conversion instruction information on the basis of the screen configuration command from the client device. When the image data is contained in the response command, the conversion instruction information can be a deletion instruction command which instructs to delete a part of pixels of the image data in a predetermined pattern.
According to the present invention, there is also provided a data relay apparatus connected to a client device through a first network and to a server device through a second network, which includes means for analyzing a command inputted from the client device, means for separating conversion instruction information from the command when the command contains the conversion instruction information instructing a conversion processing; means for transmitting the command after deletion of the conversion instruction information to the server device; means for receiving data responding to the command after deletion of the conversion instruction information from the server device; means for generating a conversion command by converting the data on the basis of the conversion instruction information; and means for transmitting the conversion command with the conversion instruction information to the client device.
According to the present invention, there is further provided a data transmission method of a network system including a data relay apparatus connected to a client device connected through a first network and to a server device through a second network, wherein the data relay apparatus analyzes a command inputted from the client device, deletes conversion instruction information from the command when the command contains the conversion instruction information instructing a conversion processing, and transmits the command to the server device, the server device which receives the command after deletion of the conversion instruction information transmits data responding to the command after deletion of the conversion instruction information, and the data relay apparatus which receives the data converts the data to generate a conversion command on the basis of the conversion instruction information, and transmits the conversion command with the conversion instruction information to the client device.
According to the present invention, there is further provided an information storage medium storing a data conversion function for data relay for use in a data relay apparatus connected to a client device through a first network and to a server device through a second network, wherein the information storage medium stores a program having a function of analyzing a command inputted from the client device, a function of deleting conversion instruction information from the command when the command contains the conversion instruction information instructing a conversion processing to the command, and transmitting the command to the server device, a function of receiving a data responding to the command after removal of the conversion instruction information from the server device, a function of generating conversion data by converting the data on the basis of the conversion instruction information, and a function of transmitting the conversion command with the conversion instruction information to the client device.
According to the present invention, there is further provided a data converting device having information output means for outputting the data after the conversion processing described above is executed and data that is newly generated.
When the kind of data is screen configuration data describing configuration of a screen output of an information processing unit, a predetermined rule provides not only mere data conversion but list display, etc. so that efficiency of grasping the content of data can be improved.
Existing servers and clients can be as such utilized. When a new function or functions are added to the present invention, these servers and clients need not be changed, and the maintenance cost can be kept low, in consequence. Since a specific server is not necessary, utility by the screen configuration expansion by the present invention can be improved for all the pages of a large number of servers to which access can be made by everyone of the world.